I can't tell from that video what kind of road that is. It's clearly not a residential street with a 30 mph limit. If it's a freeway, and since it was close to 1 in the morning with virtually no traffic on it, I don't consider that kind of speeding to be dangerous to the public. Those roads are designed to handle speeds (for emergency vehicles and such) well in excess of their posted limits.

That cop clearly has an attitude problem and should be set behind a desk if he isn't outright canned.